[Amps] MOSFET amp filtering - was: auto-tune

[Steve Wright]

On 12/12/16 10:36, various people wrote:
> What might it cost of someone made and sold a filter like this?
>
> [....]  http://www.qsl.net/wm5z/qex199907.pdf
>
>> [...]  the wrong one can hurt badly. It's not as
>> simple as looking at what the filter is presenting, there's also the
>> effects of matching circuits going back to the drains.
>>
>> With the hf bands being mostly narrow frequency segments, it should be
>> possible to tweak the filters for optimum results.

Why all the hand-wringing with this?  Surely a basic Pi output circuit 
would work well, and would be miles simpler?

Steve